Race Condition C thread - c

Question

So two threads should call two runTimes functions and runTimes function should call increase_count and decrease_count. At the end the result should be 3. The problem is that the last line of code doesn't get executed when I run the program and I can't really identify what causes the race condition.
#define MAX_RESOURCES 5
int available_resources = MAX_RESOURCES;
int times = 100000;
pthread_mutex_t mutex;
sem_t semaphore;
/* decrease available_resources by count resources
* return 0 if sufficient resources available,
* otherwise return -1 */
int decrease_count(int count) {
if (available_resources < count) {
return -1;
} else {
available_resources -= count;
printf("Locked %i resources, now available: %i\n" , count , available_resources);
return 0;
}
}
/* increase available resources by count */
int increase_count(int count) {
if (count + available_resources > 5) {
return -1;
} else {
available_resources += count;
printf("Freed %i resources, now available: %i\n" , count , available_resources);
return 0;
}
}
void *runTimes(void *null) {
int i = 0 , result;
while (i < times) {
result = -1;
while (result < 0) {result = decrease_count(1);}
result = -1;
while (result < 0) {result = increase_count(1);}
i += 1;
printf("Count; %i\n",i );
}
return NULL;
}
int main(int argc, char *argv[])
{
pthread_t thread1 , thread0;
pthread_t threads [2];
decrease_count(2);
pthread_create(&thread0, NULL, runTimes, NULL);
pthread_create(&thread1, NULL, runTimes, NULL);
int i = 0;
while( i < 2) {
pthread_join(threads[i], NULL);
i++;
}
pthread_exit(NULL);
printf("Currently available resources (should be 3): %i\n" , available_resources);
return 0;
}

Answer 1

the last line of code doesn't get executed
This is beacuse you call
pthread_exit(NULL);
before calling this
printf("Currently available resources (should be 3): %i\n" , available_resources);
(last) line.
pthread_exit() exits the current thread, that is the thread that calls function.
The race in the code you show is unrelated to this. It might occur because the code does not implement any protection against concurrently accessing the same variables.
Also you want to join the threads you created.
To do so change
pthread_create(&thread0, NULL, runTimes, NULL);
pthread_create(&thread1, NULL, runTimes, NULL);
to be
pthread_create(&threads[0], NULL, runTimes, NULL);
pthread_create(&threads[1], NULL, runTimes, NULL);